Here's what you have to eat to get a full day's worth of vitamin D

Vitamin D contributes to strong bones and protects against conditions like osteoporosis, but it can be hard to get when it’s not sunny.

While you can get some from your diet, there aren’t many foods that contain vitamin D.

Fish, eggs, and fortified foods are reliable sources of the nutrient.

Vitamin D is important for building strong bones and helps protect you from conditions like osteoporosis and psoriasis, according to the Mayo Clinic. While you get some from sunshine, you may not get all you need when it’s cloudy. You can boost your intake with your diet, but there aren’t many foods that contain vitamin D.

“Ensuring adequate vitamin D intake is tricky, considering there are many different factors absorption and activation depends upon,” Callie Exas, a registered dietitian nutritionist, told INSIDER. “That being said, there are a few hacks to maximise the utilization of dietary vitamin D in the body. Firstly, there are two types of vitamin D: D3, which is the active form, and D2, which is mostly found in plants. D3 is considered the more active form on the body while the plant form, D2, is less effective, maintaining homeostatic levels of vitamin D in the blood. Therefore, it’s important to ensure you get adequate amounts of D3 through sun exposure and the right foods.”

To make the best food choices for maximizing your vitamin D intake, you need to take into account foods that naturally contain the nutrient as well as those that are fortified with it

iStockEgg yolks contain vitamin D.

“Egg yolks are natural sources of vitamin D, supplying you with about 5% to 10% of your daily dose of vitamin D,” Maya Bach, a registered dietitian nutritionist, told INSIDER. “Stash hard-boiled eggs in your fridge for a nutrient-dense snack, add an egg to stir-fry veggies for an extra dose, or make an egg-salad sandwich to go.”

Toni Marinucci, a registered dietitian nutritionist, told INSIDER that fatty fish, such as salmon and trout, can help you get the vitamin D you need. These kinds of fish contain 400 to 650 international units of vitamin D per 3-ounce serving (the National Institutes of Health recommends adults get 600 international units of vitamin D a day).

Exas said that liver and mushrooms are good sources of vitamin D – but that only some mushrooms provide a boost

“You can get a good amount of D2 from about a cup of sun-exposed mushrooms – it’s the only plant that provides significant amounts of vitamin D,” Exas said. “Fun fact: Exposing the gills of the mushrooms to direct sunlight (not through a window) for a few days can significantly increase their vitamin D content.”

Beyond that, fortified foods can provide vitamin D.

“While not a natural source of vitamin D, cow’s milk and some plant-based milks are fortified with vitamin D,” Bach said. “While the amount varies across different brands, 1 cup will help you meet approximately 15% to 25% of your daily vitamin D need. Be sure to check the nutrition-facts label to see if your milk or milk alternative, such as soy, oat, and almond, are fortified with vitamin D.”

Marinucci said it’s important to pair foods that contain vitamin D with foods that are rich in calcium, as vitamin D helps the body absorb calcium. “Foods rich in calcium include fish, yogurt, cheese, white beans, soybeans, and cooked greens like collard, kale, or spinach,” she said.

Consult your doctor or a qualified healthcare professional about how much vitamin D you should be getting and “get a routine blood test to test your levels,” Bach said. “Check with a healthcare provider before taking any supplements. Older adults, people with certain medical conditions, breastfed infants and people with darker skin may be at risk for deficiency.”

But you don’t want to overdo it on vitamin D – it’s all about balance.